Grass collection systems on commercial mowers, particularly riding mowers, are commonly used and highly desirable, particularly when the grass is long or the turf growth has been heavy. These collection systems provide an easy means for the operator to collect and dispose of excess grass clippings. These collection systems are being made larger, and often are powered, not only by the air stream generated by the cutting blades rotating at a high speed, but also by an auxiliary blower, such as a centrifugal fan. In this manner, the grass clippings can be directed rearwardly to a large capacity collection container, so that the operator can spend more time mowing, and less time emptying the container. However, having a large container remotely mounted from the mower deck has created its own set of problems, such providing for a way to distribute the grass clippings relatively evenly within the collection container to maximize the amount of grass that can be loaded before the container needs to be emptied.
One problem that is encountered is the loading of grass clippings in one spot only in the container. The effect of concentrating the load in one area of the container is that other areas of the container, such as the corners, are not filled to their capacity. This loading problem is further exacerbated when the grass being cut is long and/or wet. At times, the outlet into the collection container may clog, and/or the chutes leading from the mower deck to the container may clog. In some grass collection systems, the clippings under certain conditions may tend to build up right in front of the chute outlet, eventually blocking the entrance of additional clippings well before the collection hopper is filled.
One widely used solution to the foregoing distribution problem has been to provide for moving baffle or arm that waves back and forth in the discharge path of outlet this chute which directs the grass to different parts of the container. This approach requires a mechanical drive system for providing the necessary reciprocating motion. Also, appropriate linkages that can withstand overloads in the event that the chute clogs must be provided as part of this drive system, since this can happen under certain circumstances, such as very wet caking grass or an overfilled hopper. This mechanical system in turn creates additional maintenance requirements, and need to take appropriate precautions to avoid creating pinch points, etc. It also adds to the cost of the collection system.
The waving arm or baffle that is inserted into the air stream also has the disadvantage of incrementally increasing the back pressure at the outlet of the discharge chute into the collection hopper, and increasing turbulence, which can help slow down the moving stream of grass clippings, and promote clogging.
Therefore, it is a primary object of the present invention to provide a passive deflector that is able to direct the grass clippings to various locations within the grass collection container so as to optimally utilize all of the space within the hopper.
It is a further object of the present invention to provide a deflector system having a favorable outlet geometry that reduces the back pressure introduced into head of the airflow from the duct outlet.
It is yet a further object of the present invention to provide a passive deflector system that utilizes no moving parts, is less expensive to provide, and easier to maintain than the deflector systems which employ a moving arm.
It is yet a further object of the present invention to provide a passive deflector that includes curved regions on a concave surface for directing a common stream of air-borne grass clippings to distinct areas within a grass collection container.
One more object is to provide an improved discharge chute geometry for a deflector that is arranged to be largely self-cleaning so as to reduce buildup and clogging at the chute outlet.